Codabar was developed in 1972 by Pitney Bowse, Inc. Codabar is a discreate, self-checking symbology. In Japan, it is called NW-7(Japanese standard JIS X0503)
Codabar has a character set of 16 letters: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -, $, :, /, ., +.
Codabar has four start/stop characters we refer here as A, B, C and D.
Codabar is used in US blood banks, photo labs, and Fedex airbills.
The minimum value of X is 7.5 mils. The wide-to-narrow (N) ratio shall be between 2.0 and 3.0 and remains constant in the symbol, and N must exceed 2.2 if X is less than 20 mils. The minimum bar height is 15 percent of the symbol length or 0.25 inches, whichever is greater.
There is no check digit required for codabar, though some applications opt to append a check digit at the end of the message.
FedEx Airbills use a variant of codabar. A FedEx airbill number has the
format of XXXX-XXXX-XXXY
with an additional 4-digit format ID. The Y
character is a check digit with the algorithm unknown to public. The
first 12 digits is the track number. The barcode itself starts with
start/stop character C and ends with start/stop character D.
A typical Codabar barcode has the following structure:
A start character from 4 choices: A, B, C and D.
Inter-character gap space
Encoded message
A stop character from 4 choices: A, B, C and D.